1. Field of the Invention
This invention relates to an analog electronic timepiece having an electric-optical display device for displaying data.
2. Description of the Related Art
In an attempt to offer multifunctional analog electronic timepieces, there have been proposed to form an opening in a dial plate and provide an electric-optical display device such as a liquid crystal display device in the opening, and to make the electric-optical display device display alternatively various information, such as date, alarming time, stop-watch measuring time, schedule, and telephone numbers, etc.
However, these known analog electronic timepieces of this type injure their appearance because display surfaces of their electric-optical display devices are always exposed even when there is no need to display information thereon.
To improve their appearance when there is no need to display information, Published Unexamined Japanese Patent Application No. 1-242987 and Published Unexamined Japanese Utility Model Application No. 1-91291 propose to provide a shutter plate for opening and closing the opening of the dial plate between the dial plate and the liquid crystal display device arranged under the opening in such a manner that a switch is operated to drive a pulse motor and thereby moving the shutter plate to expose the display surface of the liquid crystal display device in the opening only when data should be displayed on the liquid crystal display device.
With such arrangement, the appearance of the analog electronic timepiece is not injured because the electric-optical display device is covered by the shutter plate when no data is displayed thereon.
However, the appearance of the analog electronic timepiece has been still injured when the electric-optical display device is exposed in the opening of the dial plate to display date thereon.
Namely, the number of display digits in the display surface of the electric-optical display device, which are needed for displaying data, is changed by the type of information to be displayed so that the display surface have a large number of unused display digits when each of some information is displayed on the display surface. These unused display digits appeared in a large area in the display surface deteriorate the appearance of the timepiece.
For instance, an electric-optical display device needs two display digits if the data is displayed on the display surface, and needs four display digits if both the data and the month, or the alarm time are displayed, whereas six or more than six display digits are needed to display the stop watch measuring time information. Moreover, ten or more than ten display digits are required to display the schedule information or the telephone number information. Therefore, an electric-optical display device needs more than 10 display digits to alternatively display the various information including the schedule information and the telephone number information. When an electric-optical display device display information, which needs a small number of display digits to be used to display it on the display surface, such as the date of two figures or the date and month or the alarm time of four figures, more than a half of the number of the display digits in the display surface are not used, so that recognition of these information on the display surface becomes hard and the appearance of the timepiece is injured.